CN112829743B

CN112829743B - Driving assistance device

Info

Publication number: CN112829743B
Application number: CN202010959784.6A
Authority: CN
Inventors: 大竹宏忠
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2019-11-07
Filing date: 2020-09-14
Publication date: 2024-02-09
Anticipated expiration: 2040-09-14
Also published as: JP7140092B2; US11420627B2; US20210139034A1; JP2021077012A; CN112829743A

Abstract

The driving support device performs deceleration control so as to bring the vehicle to a stopped state at a target position corresponding to a deceleration target in front of the vehicle. The driving support device calculates a predicted vehicle speed of the vehicle at the target position when the deceleration control is performed, based on the current vehicle speed of the vehicle, the distance to the target position, and the deceleration that varies depending on the type of the deceleration target. When the predicted vehicle speed is greater than a predetermined value, the driving support device does not perform the deceleration control or reduces the deceleration in the deceleration control.

Description

Driving assistance device

Technical Field

The present invention relates to a driving assistance device.

Background

Conventionally, japanese patent application laid-open No. 2013-218429 has been known as a technical document on a driving support device. The publication discloses the following technique: when the current vehicle speed of the vehicle is greater than a predetermined vehicle speed that differs according to the distance to the stop line (target position) of the traffic signal (deceleration target) ahead of the vehicle, deceleration control (assist) is not performed.

Disclosure of Invention

In the driving support apparatus as described above, although the possibility that the vehicle speed of the vehicle at the target position is sufficiently high and it can be estimated that the driver does not have a deceleration idea is high in the case where deceleration control is performed, deceleration control may be performed in the same manner as in the case where deceleration idea is provided, for example, other than this.

Accordingly, an object of an aspect of the present invention is to provide a driving support device capable of suppressing deceleration control in the same manner as in other cases when there is a high possibility that the driver does not have a deceleration idea.

In one aspect of the present invention, a driving support device that performs deceleration control so that a target position corresponding to a deceleration target in front of a vehicle is in a stopped state calculates a predicted vehicle speed of the vehicle at the target position when the deceleration control is performed based on a current vehicle speed of the vehicle, a distance to the target position, and a deceleration that differs according to a type of the deceleration target, and does not perform the deceleration control or reduces the deceleration during the deceleration control when the predicted vehicle speed is greater than a predetermined value.

In this driving support device, the predicted vehicle speed of the vehicle at the target position in the case where the deceleration control is performed is calculated based on the current vehicle speed, the distance to the target position, and the deceleration that differs depending on the type of the deceleration target. If the predicted vehicle speed is greater than the predetermined value, it can be estimated that there is a high possibility that the driver does not have a deceleration idea, and therefore, the deceleration control is not performed or the deceleration in the deceleration control is reduced. This makes it possible to suppress deceleration control in the same manner as in the other cases when the driver has high possibility of not having a deceleration idea.

In the driving assistance device according to the aspect of the present invention, the predetermined value may be determined based on the type of the deceleration target and the detection likelihood of the deceleration target. In this driving support apparatus, it is possible to estimate with high accuracy that there is a high possibility that the driver does not have a deceleration idea.

In the driving support device according to an aspect of the present invention, the deceleration control may not be performed or the degree of deceleration in the deceleration control may be reduced when an accelerator operation that increases the accelerator operation amount of the vehicle is detected, when an accelerator operation of the vehicle is not detected, or when an accelerator operation that decreases the accelerator operation amount of the vehicle is not detected. In the case where an accelerator operation that increases the accelerator operation amount of the vehicle is detected, in the case where an accelerator operation of the vehicle is not detected, or in the case where an accelerator operation that decreases the accelerator operation amount of the vehicle is not detected, it is found that the possibility that the driver does not have a deceleration idea is high. In this way, in these cases, by not performing the deceleration control or reducing the deceleration in the deceleration control, it is possible to further suppress the deceleration control in the same manner as in the other cases when the possibility that the driver does not have the idea of deceleration is high.

According to an aspect of the present invention, it is possible to provide a driving assistance device capable of suppressing deceleration control in the same manner as in other cases when there is a high possibility that the driver does not have a deceleration idea.

Drawings

Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals denote like elements, and in which:

fig. 1 is a block diagram showing a configuration of a vehicle on which a driving support device according to an embodiment is mounted.

Fig. 2A is a graph illustrating an example of calculation of the predicted vehicle speed of the vehicle at the target position.

Fig. 2B is a graph illustrating an example of setting the predetermined value.

Fig. 3 is a flowchart showing an example of the processing of the driving support apparatus of fig. 1.

Detailed Description

Hereinafter, exemplary embodiments will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals, and the repetitive description will not be repeated.

Fig. 1 is a block diagram showing a configuration of a vehicle M on which a driving support device 100 according to the embodiment is mounted. As shown in fig. 1, the driving support device 100 is mounted on a vehicle M such as a passenger car, for example, and supports driving of the vehicle M. The driving support device 100 may be a device that can realize automatic driving when the vehicle M is an autonomous vehicle, or may be a device that can only perform driving support for the driver of the vehicle M.

The driving support device 100 includes an ECU (Electronic Control Unit ) 10 that collectively manages the system. The ECU10 is an electronic control unit having a CPU (Central Processing Unit ), a ROM (Read Only Memory), a RAM (Random Access Memory ), and the like. In the ECU10, for example, a program stored in a ROM is loaded into a RAM, and the CPU executes the program loaded in the RAM, thereby realizing various functions. Part of the functions of the ECU10 may also be performed in a server capable of communicating with the vehicle M. The ECU10 may be constituted by a plurality of electronic units. The ECU10 is connected to an external sensor 1, an internal sensor 2, and an actuator (actuator) 3.

The external sensor 1 is a detection device that detects a condition around the vehicle. The external sensor 1 includes at least one of a camera and a radar sensor. The camera is a photographing device that photographs an external situation of the vehicle. The camera is provided, for example, on the rear side of a windshield of the vehicle, and photographs the front of the vehicle. The camera transmits photographing information about the external condition of the vehicle to the ECU 10. The camera can be a monocular camera or a stereo camera. A radar sensor is a detection device that detects an object around a vehicle using electric waves (e.g., millimeter waves) or light. Radar sensors include, for example, millimeter wave radar or laser radar (LIDAR: light Detection and Ranging). Radar sensors detect an object by transmitting an electric wave or light to the surroundings of a vehicle and receiving the electric wave or light reflected by the object. The radar sensor transmits information of the detected object to the ECU 10. In addition to fixed obstacles of guardrails, buildings, etc., objects include moving obstacles of pedestrians, bicycles, other vehicles, etc.

The internal sensor 2 is a detection device that detects a running state of the vehicle. The internal sensor 2 includes a vehicle speed sensor or an acceleration sensor. The internal sensor 2 may also comprise a yaw rate sensor. The vehicle speed sensor is a detector that detects the speed of the vehicle. As the vehicle speed sensor, for example, a wheel speed sensor provided for a wheel of a vehicle or a propeller shaft or the like that rotates integrally with the wheel and detecting the rotation speed of the wheel may be used. The vehicle speed sensor transmits detected vehicle speed information (wheel speed information) to the ECU 10.

The acceleration sensor is a detector that detects acceleration of the vehicle. The acceleration sensor includes, for example, a front-rear acceleration sensor that detects acceleration in the front-rear direction of the vehicle, and a lateral acceleration sensor that detects lateral acceleration of the vehicle. The acceleration sensor transmits acceleration information of the vehicle to the ECU10, for example. The yaw rate sensor is a detector that detects a yaw rate (rotational angular velocity) of a plumb axis around the center of gravity of the vehicle. As the yaw rate sensor, for example, a gyro sensor may be used. The yaw rate sensor transmits the detected yaw rate information of the vehicle to the ECU 10.

The actuator 3 is an apparatus used in control of the vehicle. The actuator 3 includes at least a drive actuator, a brake actuator, and a steering actuator. The drive actuator controls the amount of air supplied to the engine (throttle opening) in response to a control signal from the ECU10, and controls the driving force of the vehicle. In addition, when the vehicle is a hybrid vehicle, a control signal from the ECU10 is input to a motor as a power source in addition to the supply amount of air to the engine, and the driving force is controlled. In the case where the vehicle is an electric vehicle, a control signal from the ECU10 is input to a motor as a power source, and the driving force is controlled. The motor as a power source in these cases constitutes the actuator 3.

The brake actuator controls a brake system according to a control signal from the ECU10 to control braking force applied to wheels of the vehicle. As the brake system, for example, a hydraulic brake system may be used. The steering actuator controls driving of an assist motor that controls steering torque in the electric power steering system, in accordance with a control signal from the ECU 10. Thereby, the steering actuator controls the steering torque of the vehicle.

The ECU10 performs deceleration control so that the target position corresponding to the deceleration target in front of the vehicle M is brought into a stopped state. The deceleration target is not particularly limited, and includes various objects. For example, another vehicle traveling ahead of the vehicle M (hereinafter also referred to as a "preceding vehicle"), a stop line, a traffic signal, and the like may be cited as the deceleration target. The type of the preceding vehicle and the like are not particularly limited, and may be various types and the like. The stop line is a road surface mark that is a target of a position where the vehicle is stopped or temporarily stopped. The traffic signal is a device for indicating a signal such as a travel permission and a stop instruction for ensuring traffic safety or smoothing traffic flow, and includes a vehicle signal facing the vehicle M toward the front. The annunciator herein may not include an annunciator oriented inward or laterally with respect to the vehicle M. The form of the annunciator and the like are not particularly limited, and various forms and the like are possible.

The deceleration control is control for decelerating the vehicle M at a deceleration different depending on the type of the deceleration target, and bringing the vehicle M into a stopped state at the target position. The type of the deceleration target can be identified by a known method based on the detection result of the external sensor 1, for example. The stopped state refers to a state in which the vehicle speed of the vehicle M is 0km/h or the vehicle speed is less than a stopped state threshold. The stop state threshold is a threshold value of a preset value. The stop-state threshold may be, for example, 5km/h or 3km/h.

The target position corresponding to the deceleration target is a target position for bringing the vehicle M to a stopped state, which is determined according to the type and state of the deceleration target. The target position corresponding to the deceleration target is a position near the deceleration target. The target position corresponding to the deceleration target can be determined by a known method based on at least one of the type of deceleration target identified and the detection result of the external sensor 1, for example. For example, the target position when the deceleration target is the preceding vehicle is the position immediately before the preceding vehicle. For example, the target position when the deceleration target is the stop line is a position immediately before the stop line. For example, the target position when the deceleration object is the annunciator is a position immediately before the annunciator.

As an example, when the deceleration of the preceding vehicle is the 1 st deceleration, the deceleration of the stop line is the 2 nd deceleration, and the deceleration of the signal is the 3 rd deceleration, the 1 st deceleration > the 2 nd deceleration > the 3 rd deceleration. The reason why the 2 nd deceleration > the 3 rd deceleration is considered to be due to: when comparing the annunciator with the stop line, it is considered that in the stage in which the annunciator is detected, the degree of determination of the stop position is small (it is possible to be re-covered by finding the stop line) as compared with the stage in which the stop line is detected. The reason why the 1 st deceleration > the 2 nd deceleration is because: the detection of the stop line is later than the detection of the preceding vehicle (there is a possibility of erroneous recognition due to lack of height, wear, and the like). In addition, due to the fact that: the risk of being unable to stop immediately before the stop line is smaller than the risk of being unable to stop immediately before the preceding vehicle. The deceleration that differs depending on the type of the deceleration target may be a fixed value or a variable value. The deceleration corresponding to the deceleration target can be obtained, for example, from a data table, an arithmetic expression, a model for calculating the deceleration, or the like, which is determined for each deceleration target in advance, based on the identified type of the deceleration target.

The ECU10 performs deceleration control (outputs a control signal to the actuator 3) when, for example, a deceleration target is identified based on the detection result of the external sensor 1. The deceleration control is not particularly limited, and may be any other known deceleration control as long as the vehicle M is decelerated so that the target position corresponding to the deceleration target in front of the vehicle M is brought into a stopped state.

The ECU10 calculates a predicted vehicle speed (hereinafter also simply referred to as "predicted vehicle speed") of the vehicle M at the target position in the case where the deceleration control is performed, based on the current vehicle speed of the vehicle M, the distance to the target position, and the deceleration that differs depending on the type of the deceleration target. The current vehicle speed of the vehicle M can be obtained based on the detection result of the internal sensor 2, for example. The distance to the target position can be obtained based on the detection result of the external sensor 1, for example. For example, in the example shown in fig. 2A, the vehicle speed of the vehicle M is decelerated at a deceleration of a predetermined value as the distance to the target position becomes smaller by executing deceleration control. The vehicle speed at the point (asterisk in the figure) at which the distance to the target position in the figure is 0 is calculated as the predicted vehicle speed. Further, the road surface gradient of the road on which the vehicle M is traveling may be considered in order to calculate the predicted vehicle speed. The road surface gradient can be obtained using the detection result of the external sensor 1, for example. Regarding the consideration of the road surface gradient for the predicted vehicle speed, this can be achieved by a known method, for example.

When the predicted vehicle speed is greater than the predetermined value, the ECU10 does not perform the deceleration control or reduces the deceleration in the deceleration control. Not performing the deceleration control means, for example, bringing the deceleration control to a stopped state and prohibiting execution of the deceleration control. Reducing the deceleration means changing the deceleration of the deceleration control from the currently set deceleration to a deceleration lower than the currently set deceleration by a predetermined amount. The predetermined amount is not particularly limited, and may be a predetermined fixed amount or a fluctuation amount. Reducing the deceleration means, for example, moderating (weakening) the deceleration control. In other words, reducing the deceleration in the deceleration control means that low deceleration control, which is deceleration control that reduces the deceleration, is performed instead of normal deceleration control.

The predetermined value is a value determined according to the type of the deceleration object and the detection likelihood (likelihood) of the deceleration object. Such a predetermined value can be set as follows, for example. That is, first, the ECU10 obtains the detection likelihood of the deceleration target from the detection result (for example, the captured image of the camera) of the external sensor 1. Specifically, in the case where the deceleration target is identified as the annunciator, when red or yellow can be identified as the lamp color and no arrow signal can be identified, the detection likelihood is set to "high". When the deceleration target is identified as a traffic signal, the detection likelihood is set to "high" when red or yellow can be identified as a lamp color and it is determined that the vehicle cannot proceed straight according to the arrow direction of the arrow signal. When the deceleration target is identified as a traffic signal, the detection likelihood is set to "medium" when red or yellow can be identified as a lamp color and the presence or absence of an arrow signal is unknown. When the deceleration target is identified as a traffic signal, the detection likelihood is set to "low" when red or yellow can be identified as a lamp color and an arrow signal is identified but the direction of the arrow is not determined. Further, for example, as shown in fig. 2B, the ECU10 determines the predetermined value to be proportionally larger as the detection likelihood is higher. The predetermined value is not particularly limited, and may be a predetermined fixed value or may be determined only by the type of the deceleration target. The detection likelihood is also referred to as detection confidence.

For example, when the deceleration target is recognized as the traffic signal, if red or yellow is not recognized as the lamp color, the ECU10 does not perform the deceleration control or reduces the deceleration in the deceleration control. The ECU10 detects an accelerator operation of the vehicle M, for example, based on a detection result of an accelerator sensor or the like. The detected accelerator operation includes the presence or absence of an accelerator operation that increases the accelerator operation amount of the vehicle M (for example, the presence or absence of an operation to depress the accelerator pedal), the presence or absence of an accelerator operation of the vehicle M itself (for example, whether the accelerator pedal is not operated), and the presence or absence of an accelerator operation that decreases the accelerator operation amount of the vehicle M (for example, the presence or absence of an operation to return the accelerator pedal). When the accelerator operation to increase the accelerator operation amount of the vehicle M is detected, when the accelerator operation to decrease the accelerator operation amount of the vehicle M is not detected, or when the accelerator operation to decrease the accelerator operation amount of the vehicle M is not detected, the ECU10 does not perform the deceleration control or decreases the deceleration in the deceleration control as the accelerator operation matches the accelerator operation condition (the condition of the accelerator operation that is satisfied when the driver does not have the deceleration intention or the deceleration intention is small) when the deceleration intention is not present.

Next, an example of the processing of the ECU10 in the driving support apparatus 100 will be described with reference to the flowchart of fig. 3. In the following, a case where the deceleration target is a traffic signal will be described as an example.

The ECU10 determines whether the lamp color of the traffic signal is red or yellow based on the detection result of the external sensor 1 when the traffic signal is recognized based on the detection result, for example, when the vehicle M is traveling in a state where driving assistance is permitted or when the vehicle M is in automatic driving (step S1). In the case of yes in step S1 described above, the ECU10 determines whether or not the accelerator operation of the vehicle M coincides with the accelerator operation condition when there is no intention to decelerate (step S2). If no in step S2, the ECU10 calculates the predicted vehicle speed and determines whether the predicted vehicle speed is equal to or less than a predetermined value (step S3). If yes in step S3, the ECU10 allows deceleration control to perform deceleration control as described above (step S4). On the other hand, if no in the above step S1, yes in the above step S2, or no in the above step S3, for example, as the driver having no deceleration intention or little deceleration intention (having the intention of desiring to pass the holding state unchanged), the deceleration control is not permitted, and the deceleration control is not performed (step S5). In addition, in the above step S5, instead of not performing the deceleration control, the deceleration in the deceleration control may be reduced.

As described above, in the driving support device 100, the deceleration control is performed so that the target position corresponding to the deceleration target in front of the vehicle M is brought into the stopped state. Here, when the predicted vehicle speed of the vehicle M at the target position at the time of deceleration control is greater than the predetermined value, it can be estimated that there is a high possibility that the driver does not have a deceleration idea, and therefore the deceleration control is not performed or the deceleration in the deceleration control is reduced. This makes it possible to suppress the deceleration control in the same manner as in the other cases when the driver has a high possibility of not having a deceleration idea.

In the driving assistance device 100, the predetermined value is determined according to the type of the deceleration object and the detection likelihood of the deceleration object. In the driving support apparatus 100, it is possible to estimate with high accuracy that there is a high possibility that the driver does not have a deceleration idea.

The driving assistance device 100 does not perform deceleration control or reduces the degree of deceleration in the deceleration control when an accelerator operation that increases the accelerator operation amount of the vehicle M is detected, when an accelerator operation of the vehicle M is not detected, or when an accelerator operation that decreases the accelerator operation amount of the vehicle M is not detected. In the case where the accelerator operation that increases the accelerator operation amount of the vehicle M is detected, in the case where the accelerator operation of the vehicle M is not detected, or in the case where the accelerator operation that decreases the accelerator operation amount of the vehicle M is not detected, it is found that the possibility that the driver does not have a deceleration idea is high. In this way, in these cases, by not performing the deceleration control or reducing the deceleration in the deceleration control, it is possible to suppress the deceleration control from being performed in the same manner as in the other cases when the possibility that the driver does not have the idea of decelerating is high.

The embodiments have been described above, but one embodiment of the present invention is not limited to the above-described embodiments. The present invention has been made in view of the above-described embodiments, and can be implemented in various ways by various modifications and improvements based on knowledge of those skilled in the art.

In the above embodiment, the map information in the map database may be used in each process of the driving support apparatus 100. In the above embodiment, the information acquired by at least one of the inter-vehicle communication and the road-vehicle communication may be used in each process of the driving support device 100. In the above embodiment, the positional information of the vehicle M acquired by GPS (Global Positioning System ), GNSS (Global Navigation Satellite System, global navigation satellite system), SLAM (Simultaneous Localization and Mapping ) or the like may be used in each process of the driving support apparatus 100. In the above description, "decreasing the deceleration" means "decreasing the absolute value of the acceleration".

Claims

1. A driving support device performs deceleration control so that a vehicle is brought into a stopped state at a target position corresponding to a deceleration target in the front of the vehicle when the deceleration target is identified,

the driving assistance device calculates a predicted vehicle speed of the vehicle at the target position in the case where the deceleration control is performed, based on a current vehicle speed of the vehicle, a distance to the target position, and a deceleration that differs according to a type of the deceleration target,

the driving assistance device does not perform the deceleration control or reduces the deceleration in the deceleration control when the predicted vehicle speed is greater than a predetermined value.

2. The driving assistance device according to claim 1,

the predetermined value is determined according to the class of the deceleration object and the detection likelihood of the deceleration object.

3. The driving assistance device according to claim 1 or 2,

if an accelerator operation that increases the accelerator operation amount of the vehicle is detected, if an accelerator operation of the vehicle is not detected, or if an accelerator operation that decreases the accelerator operation amount of the vehicle is not detected, the deceleration control is not performed or the deceleration in the deceleration control is decreased.